Brain & Behavior Chapter 8
environmental cue that resets a biological clock
A "zeitgeber" is a(n)
seasons other than migration
A decrease the amount of sleep most likely to affect the performance of migratory bird during
jetlag
A disruption of circadian rhythms due to crossing time zones is known as
interrupted or shortened REM sleep
A person who is taking an antidepressant that increases serotonin or norepinephrine levels in the brain is most likely to have
spends a period of time in seclusion, away from sunlight
A person's circadian activity cycle would most likely drift out of phase with the activity of other people if the person
a combination of EEG and eye-movement records
A polysommonograph displays ___
to shake the eyeballs back and forth in order to get sufficient oxygen to the corneas of the eyes
A recent hypothesis proposed that the role of REM is
retinohypothalamic
A small branch of the optic nerve, down as the _____ path extends directly from the retina to the SCN
the brain's attempt to make sense of spontaneous neural activity
According to the activation - synthesis hypothesis, what do dreams reflect?
enters a prolonged state of sleep
After a cut through the midbrain separates the forebrain and part of the midbrain from all the lower structures, an animal
still has rhythms, but they are less consistent
After damage to the suprachiasmatic nucleus, the body
cycles back through stages 3 and 2
After entering stage 4 for the first time each evening, the sleeper typically
SCN
After isolating neuron from the rest of the brain, you find that it has a moderately stable circadian rhythm. The most likely home of this neuron is in the
relaxed wakefulness
Alpha waves are are characteristic of what type of activity?
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Among adult humans, those who sleep _____ or more hours per night have the highest percentage of REM sleep
They sleep poorly during rest periods.
An astronaut orbiting earth experiences 45-minute periods of daylight alternating with 45-minutes periods of darkness. What is likely to happen?
a net average of all neuron's potentials
An electroencephalograph displays
about a day
Animals produce endogenous circadian rhythms that last
just over 24 hours
Based on research, it has been determined that the human circadian rhythm appears to be
acetylcholine
Cells in the basal forebrain increases arousal and wakefulness by releasing
important for strengthening memories of lists of words
Compared to REM, research suggests that NREM is
includes a larger percentage of REM sleep
Compared to the earlier part, the later part of a night's sleep
irregular, low-voltage fast waves
During REM sleep, the EEG shows
REM sleep
During ___, cells in the pons send messages that inhibit the motor neurons that control the body's large muscles.
increased firing by GABA neurons
During sleep, what happens in the brain?
neurons are becoming more synchronized
EEG waves are larger when brain activity decreases because
90 minutes
For a normal person, about how long does a cycle of sleep (from stage 1 to stage 4 and back again) last?
continue to produce activity that follows a circadian rhythm
If suprachiasmatic nucleus neurons are disconnected from the rest of the brain, they
the more total sleep, the higher the percentage of REM sleep
If we compare either different species or different ages, what trend emerges?
are more likely to include complicated plots
In comparison to NREM dreams, REM dreams
norepinephrine
In responce to emotionally arousing events, the locus coeruleus releases
acting out our dreams
It appears from research with cats that one function of the messages from the pons to the spinal cord is to prevent us from
narcolepsy
Loss of orexin-containing neurons in the hypothalamus may contribute to
for a variety of activities, including sleep
Mammals have circadian rhythms
occur during NREM sleep
Night terrors can be distinguished from nightmares in that night terrors
pontomesencephlalon
One part of the reticular formation that contributes to cortical arousal is known as the
staying awake
Orexin, produced by neurons in the hypothalamus, appears to be necessary for
REM sleep
PGO waves are associated with
move vigorously during REM, apparently acting out their dreams
People with REN behavior disorder
strengthen the formation of new motor skills
REM sleep has shown to
PGO waves in the brain
REM sleep in associated with
periodic limb movement disorder
Repeated involuntary movements of the arms and legs that may prevent a person from the falling asleep are known as
increased both in the pons and the limbic system
Research found that during REM sleep, activity
expose them to bright lights while they work
Research on circadian rhythms has shown that one of the best ways to increase the alertness and efficiency of workers on night shifts is to
most important for strengthening memories of motor skills
Research suggests that REM is
exposure of the eyes to light
Researchers have demonstrated that the expression of the SCN genes can be changed through
Stage 2
Sleep spindles and K- complexes are most characteristics of which sleep stage?
stages 3&4
Slow-wave sleep is comprised of
zeitgebers
Social stimuli - that is, the effects of other people - are weak ____, unless they induce exercise or other vigorous activity.
block histamine
Some drugs used to treat allergies may produce drowsiness if they
awakens a sleeping individual
Stimulation of the pontomesencephlalon
melatonin
The pineal gland releases ____ the hormone, which influences both circadian and cricannual rhythms.
building up during the day and declining during sleep
The protein PER and TIM, originally discovered in insect but now found in mammals also, influence circadian rhythms by
are more frequent and vivid in REM sleep
The relationship between sleep stage and dreaming is that dreams
men who are overweight
The risk of sleep apnea is increased among which group of people
only one of the several systems involved in arousal
The role of the reticular formation in arousal is that it is
pons. lateral geniculate nucleares, and occipital cortex
The sequence of the bursts of neural activity during Rem sleep is
hypothalamus
The suprachiasmatic nucleus is found in the
stage 1 and slowly progresses through stages 2,3, and 4 in order
Typically, a person who falls asleep enters
hypnagogic hallucinations
What are the dreamlike experiences at the onset of sleep that are difficult to distinguish from reality?
irregular waves with low amplitude
What do the EEG waves look like when brain activity is "desynchronized"?
generated from within
What does "endogenous" mean?
Animals' activity patterns become less consistent and no longer respond to light and dark cycles.
What happens after damage to the suprachiasmatic nucleus itself?
difficulty falling asleep
What is a likely consequence if someones temperature rhythm is phase- delayed?
consistently feeling sleepy during the day
What is a typical characteristic of insomnia?
mid to late afternoon
a human's body temperature over the course of 24 hours is usually highest
sleep spindles
another aspect of sleeps contribution to memory relates to
an attack of muscle weakness while awake
what does cataplexy involve
sudden periods of sleepiness during the day
what is narcolepsy
a high level of brain activity
REM sleep is characterized by which of the following?
vegetative
Somene in a(n) ____ state alternates between periods of sleep and moderate arousal, although even during the more aroused state, the person shows no awareness of surroundings and no purposeful behavior
Part of the brain is still asleep
Sometimes people find themselves unable to move their postural muscles immediately after awakening.WHY?
remain relatively stable
Suppose you fell into a cave and lost your watch. Without any time cues, your circadian rhythm would
They will follow the usual rhythm of 24 hours.
Suppose you work on a submarine with only artificial light. You are required to follow a schedule of working for 12 hours and then sleeping for 6. What rhythm, if any, will your alertness and body temperature show?
when the proteins reach a high level, they turn of the genes that produce them
The PER and Tim proteins accumulate during the day until they cause sleepiness. What prevents them from continuing to accumulate at night?
Optic chiasm
The SCN is located just above the
production of proteins
The SCN produces circadian rhythms by altering
reticular formation
The __ is a structure that extends from the medulla into the forebrain.
respond directly to light, but respond slowly
The circadian rhythm is reset by the ins from the ganglion cells in the retina. These ganglion cells are unusual in that they
ganglion cells that are not connected to any cones or rods
The input from the eyes to the suprachiasmatic nucleus, responsible for the shifting phase of the circadian rhythm, originates from
it is light sleep in some ways and deep in other ways
What is paradoxical sleep?
Wake them up during REM sleep and ask them if they have been dreaming
What is the best way to determine if an individual who claims to never dream does, in fact, have dreams?
light
What is the principal zeitgeber for land animals?
Is neurons generate a 24-hour rhythm by themselves
What is the role of the suprachiasmatic nucleus in the circadian rhythms?
a couple hours before the person naturally falls asleep
When do the secretions of melatonin begin?
during both stage 3 and 4 sleep
When does sleep walking occur?
The biological clock is insensitive to most forms of interference
When studying disruptions to the biological clock in animals, what did Curt Richter find?
Travel to the west is easier.
When traveling across time zones, how does the direction of travel affect one's adjustment to the new time zone?
The function of sleep is similar of that hibernation
Which claim is most consistent with the evolutionary perspective of sleep?
narcolepsy
Which condition has often been interpreted as an intrusion of REM sleep into wakefulness
a clinico-anatomical hypothesis
Which hypothesis/theory suggests that the primary motor cortex is suppressed so arousal during sleep cannot lead to action?
being obese
Which of the following increases risk of sleep apnea
sleep
Which of the following is most clearly under the control of a circadian rhythm in most animals?
keeping the room light when you need to stay awake
Which of the following would most likely help someone adjust to jet lag?
periods without breathing during sleeping
Which of these is a characteristic of sleep apnea
It is highly consistent in a given individual in a given environment
Which statement is TRUE with regard to the duration of a self-generated sleep/activity cycle?
slow, large-amplitude waves increase in number
With each succeeding stage of the sleep (from 1-4)
almost completely inactive during sleep
With regard to sleep and arousal, the locus coeruleus is
memory
Young adults deprived of a nights sleep show deficits on tasks
